What temperatures can consumer-level DSLRs and lenses typically handle? Are there any precautions one should take too minimize potential problems (e.g. condensating water)? What about moving in and ...

Title basically speaks for itself: How do you protect your equipment when you are shooting in severe conditions? Rain? Severe heat/cold? Snow? Fog? ... Other? What sorts of techniques do you use to ...

With some effort, it's possible to find out which camera models and lens have weather sealing. However, there seems to be little information available on weather-sealed flashes.
From another answer ...

I am kinda torn between buying a Sigma 18-35mm f1.8, Nikkor 17-55 f2.8 and Sigma 17-50 f2.8 for my D3100 and D7100 cameras. The reason for confusion is that the Nikkor one has a weather sealing ring ...